The problem occurs in the design configuration step of Pondmaker. The 1, 2, 5, 10, 25, and 50 yr storm events are working properly. In these cases, the pond inflow is greater than the target outflow indicating the need for a basin. However, for the 100yr storm event, this flips and the inflow is less than the target outflow. When this happens, there is an error when the storage estimate is computed and a basin cannot be designed.
The first thing I did was decrease the output increments from 3 min to 1 min. This did help a little, but the inflow is still less than the outflow.
In the attached file, you will see my model with two basins. Basin 10 is the basin with this specific problem. In addition, you will see Basin 9.
Now Basin 9 has a similar problem that I've run into before. Here, all the storms have a pond inflow less than the target inflow. To me, this means that a basin is not necessary for this given situation. I just want to verify that this is true.
Thank you in advance for your help
SWB9,10.zip
Answer Verified By: Sushma Choure